Urgent brake rotor question

[Jay 535i]

I don't know much about brake rotors, but they all seem like similar hunks of metal to me.

I have Pagid brake pads that my local mechanic said he'd be happy to install, but he says he won't machine my rotors for me because, according to him, the practice is out of favour. My rotors aren't badly warped, but I thought it would be good to freshen them up before the new pads go on. They're not smooth to the touch, and there's the slightest hint of developing warpage through the pedal.

Should I leave my rotors as they are and just install the new pads? Should I take my rotors to someone who will machine them? Should I just get new rotors, as he suggests. If so, is there anything wrong with his generic items?

Ebay is full of stuff like this:

http://cgi.ebay.com/ebaymotors/BMW-E34-525i-530i-535i-Brembo-Rotors-X-S-F-R_W0QQcmdZViewItemQQcategoryZ33564QQitemZ799755082 8QQrdZ1QQsspagenameZWDVW

Is that overkill? The thing is, I need to get my car sorted urgently. I guess the answer I want to hear is, "go ahead and use his generic rotors -- they're all much the same", but I don't wanna put crap on my car. The car currently has his generic rotors, which work fine, but I have no basis of comparison.

Advice, please.

[Dash01]

Being pleased and impressed with the quality of the stock OEM rotors and brakes, I'm wary of substituting "generic" rotors.

In any event, your stock rotors should have a minimum legal thickness dimension cast onto the back side, which will tell you if there is still enough metal to machine them on a lathe. This should cost ~$10-15 per rotor at any auto parts store with a lathe.

So, your old rotors are thick enough for re-surfacing, or they are not. If so, just "turn" them on a lathe and re-install with your new Pagid pads. If not, then look to BMA or other reputable BMW parts supplier for a decent price on OEM replacement of good quality, or at least as a cross-check of your mechanic's pricing.

[632 Regal]

get bailo or brembos, their both good. I wouldnt machine the old ones.

[93-525i]

If I was going to go for new rotors I would get the ebay brembos over the standard ones. This is especially the case if I'm running a pad that has a harder than stock compound as your rotors are more likely to warp if you don't have anywhere for the heat to go.
If you don't want to spend the money I would get the rotors machined. You's not really taking a signinficant amount of metal away so you'll be fine. The more metal you take away though, if you machine your rotors more than a couple times will warp your rotors because the lack of rotor mass will make it harder for the rotor to dissipate the heat.

[Bill R.]

car, the maximum amount that you can remove from a brand new bmw rotor is .8 mm or approx .031 thousands of an inch. If you have any wear at all to speak or or especially if you can feel warpage when you apply the brakes then you will go well beyond that limit when machining. For the price of a new set of Balo or Ate rotors from BMA i wouldn't even consider turning them unless they are in very good condition and your only turning to clean the surface. Since you mentioned warped that pretty much eliminates that possibility... As far as wasting your money on the brembo's... They are exactly the same size as the stock rotors so you don't gain any thermal mass and drilling holes in them and cutting slots actually reduces thermal mass.. I think the Balo's are about 40 dollars each from BMA and the brembo's on ebay are 200? I can buy rotors, wear indicators and Raybestos QS ceramic or Akebono ceramic pads for less than that for everything.








I don't know much about brake rotors, but they all seem like similar hunks of metal to me.

I have Pagid brake pads that my local mechanic said he'd be happy to install, but he says he won't machine my rotors for me because, according to him, the practice is out of favour. My rotors aren't badly warped, but I thought it would be good to freshen them up before the new pads go on. They're not smooth to the touch, and there's the slightest hint of developing warpage through the pedal.

Should I leave my rotors as they are and just install the new pads? Should I take my rotors to someone who will machine them? Should I just get new rotors, as he suggests. If so, is there anything wrong with his generic items?

Ebay is full of stuff like this:

http://cgi.ebay.com/ebaymotors/BMW-E34-525i-530i-535i-Brembo-Rotors-X-S-F-R_W0QQcmdZViewItemQQcategoryZ33564QQitemZ799755082 8QQrdZ1QQsspagenameZWDVW

Is that overkill? The thing is, I need to get my car sorted urgently. I guess the answer I want to hear is, "go ahead and use his generic rotors -- they're all much the same", but I don't wanna put crap on my car. The car currently has his generic rotors, which work fine, but I have no basis of comparison.

Advice, please.

[Jay 535i]

car, the maximum amount that you can remove from a brand new bmw rotor is .8 mm or approx .031 thousands of an inch. If you have any wear at all to speak or or especially if you can feel warpage when you apply the brakes then you will go well beyond that limit when machining. For the price of a new set of Balo or Ate rotors from BMA i wouldn't even consider turning them unless they are in very good condition and your only turning to clean the surface. Since you mentioned warped that pretty much eliminates that possibility... As far as wasting your money on the brembo's... They are exactly the same size as the stock rotors so you don't gain any thermal mass and drilling holes in them and cutting slots actually reduces thermal mass.. I think the Balo's are about 40 dollars each from BMA and the brembo's on ebay are 200? I can buy rotors, wear indicators and Raybestos QS ceramic or Akebono ceramic pads for less than that for everything.

Thanks for that.

Is there any major disadvantage to just leaving the rotors for now and replacing them in a month or two? Will I be ruining my new pads?

[Bill R.]

wear a pattern of grooves into the new pads... I would also get wear indicators and new rotor retaining bolts since one or more will probably not want to come out...





Thanks for that.

Is there any major disadvantage to just leaving the rotors for now and replacing them in a month or two? Will I be ruining my new pads?

[Jay 535i]

Just for fun, I called my local BMW dealer for a quote on new rotors -- just the parts, no installation.

The quote was CDN$110 for one rear rotor. The fronts are more.

As if!

[Bill R.]

webstie Bruno's Racing King


(http://www.racingking.net/Canada/scripts/default.asp)



Just for fun, I called my local BMW dealer for a quote on new rotors -- just the parts, no installation.

The quote was CDN$110 for one rear rotor. The fronts are more.

As if!

[SharkmanBMW]

watch out for aftermarket zimmerman rotors... i think warped mine during bed in....
please see new post!

[Lennyz525i]

I've got brembos on the front. I really don't like em too much, lots of brake dust but i can't really say the breaking performance is all that great.

[Jeff N.]

argh...THUD THUD THUD. This is not that hard - don't fall for the ebay hype.

Listen to Bill and Jeff
- order some balos from Racing King or BMA
- stuff in some new pads at the same time again from RK or BMA
- if you're doing the fronts, order 2 new set screws as well
- stuff in a new brake sensor too

Rotors should be about $50 to $60 USD each
Pads should be $40 to $60 per axle depending on what you order
Set screws are $1 each, one for each front rotor
A sensor is about $5 each and you'll need one per axle

Easy DIY job. Or, can't be more than about 1.5 to 2 hours per axle on the book rate.

Jeff

[Jay 535i]

argh...THUD THUD THUD. This is not that hard - don't fall for the ebay hype.

Listen to Bill and Jeff
- order some balos from Racing King or BMA
- stuff in some new pads at the same time again from RK or BMA
- if you're doing the fronts, order 2 new set screws as well
- stuff in a new brake sensor too

Rotors should be about $50 to $60 USD each
Pads should be $40 to $60 per axle depending on what you order
Set screws are $1 each, one for each front rotor
A sensor is about $5 each and you'll need one per axle

Easy DIY job. Or, can't be more than about 1.5 to 2 hours per axle on the book rate.

Jeff

Okay, will do.

[SharkmanBMW]

I've got brembos on the front. I really don't like em too much, lots of brake dust but i can't really say the breaking performance is all that great.


The dust is from the pad, not the rotor

[1995 525i]

Okay, will do.
If you do the job yourself, takes pictures and post them.

:)

[Jay 535i]

If you do the job yourself, takes pictures and post them.

:)

Don't think I will. It's cheaper and easier to pay someone else to do it.

[1995 525i]

Don't think I will. It's cheaper and easier to pay someone else to do it.
Story of my life brother.